This invention relates to a propeller assembly, and in particular, a propeller assembly for a marine vehicle.
It is known to propel a marine vehicle utilizing a propeller assembly mounted on rotatable drive shaft. The propeller assembly includes propeller blades extending radially from a central hub. A motor rotates the drive shaft which, in turn, rotates the propeller blades propelling the marine vehicle through the water.
Typically, the propeller assembly is constructed as a unit wherein the propeller blades and the central hub are mounted or removed from the drive shaft in unison. Alternatively, in order to reduce the time and costs associated with replacing the propeller blades, it has been contemplated to provide a propeller assembly for a marine engine wherein the propeller blades project from a propeller housing that is removable from a central hub. For example, LoBosco et al, U.S. Pat. No. 5,252,028 discloses a marine propeller assembly having a propeller housing which is slidably receivable on a central hub in order to be rotated therewith. The central hub is mounted on the propeller shaft and a retaining disc is threaded onto the propeller shaft to retain the propeller housing on the central hub. It has been determined, however, that the retainer disc does not adequately retain the propeller housing on the central hub such that the propeller housing may become inadvertently disengaged from the central hub resulting in the propeller housing falling from the propeller shaft during use.
Chen, U.S. Pat. No. 5,967,751 also discloses a marine propeller assembly. The propeller assembly includes a central hub secured to the propeller shaft and having three or more axially extending keys on the outer surface thereof. A propeller housing includes an inner surface having three or more pairs of lobes for forming keyways which receive the keys of the central hub. A retainer disc is threaded on a propeller shaft and includes a plurality of angularly spaced ears for engaging with the lobes on the inner surface on the propeller housing in order to prevent the propeller housing from being disengaged from the central hub.
As described, the propeller assembly disclosed in the Chen ""751 patent overcomes the limitations of the structure disclosed in the LoBosco et al ""028 patent. However, it has been found that the keys extending from the central hub have a tendency to become stuck within the corresponding keyways along the inner surface of the propeller housing. As a result, it may be difficult for an individual to remove the propeller housing from the central hub during maintenance, replacement or the like.
Further, it is highly desirable to retain the propeller housing on the central hub in such a manner to prevent any unnecessary movement of the propeller housing which may reduce the efficiency of the propeller assembly. The structure disclosed in the Chen ""751 patent includes a retainer disc having a plurality of angularly spaced ears which engage lobes and stops on the inner surface of the propeller housing in order to prevent the propeller housing from becoming disengaged from the central hub. However, due to manufacturing constraints, the ears may not tightly engage corresponding lobes and/or stops along the inner surface of the propeller housing thereby allowing for the possible movement of the propeller housing during use. As such, it is highly desirable to provide a locking mechanism for securely retaining the propeller housing on the central hub.
Therefore, it is a primary object and feature of the present invention to provide a propeller assembly which may be securely mounted to a propeller shaft of a marine vehicle.
It is a still further object and feature of the present invention to provide a propeller assembly which is simple and inexpensive to manufacture.
It is a still further object and feature of the present invention to provide a propeller assembly which incorporates a propeller housing which may be simply and easily mounted on a central hub which, in turn, is retained on a propeller shaft of a marine vehicle.
In accordance with the present invention, a propeller assembly is provided for mounting on a rotatable propeller shaft of a watercraft. The propeller assembly includes a central hub mounted on a propeller shaft for rotational movement therewith. The central hub defines a generally cylindrical outer surface having a plurality of circumferentially spaced keys therealong. A generally tubular propeller housing is slidable on the central hub for rotational movement with the propeller shaft. The propeller housing includes an inner surface having a plurality of circumferentially spaced pairs of axially extending lobes therealong. Each pair of lobes define a corresponding keyway for receiving a corresponding key along the central hub. A locking ring is mountable on the propeller shaft. The locking ring includes a generally central disc having an aperture for receiving the propeller shaft therethrough and an outer rim for engaging the lobes and preventing removal of the propeller housing from the central hub.
It is contemplated to provide a stop member on the outer end of one of the keys. The stop member limits movement of the propeller housing onto the central hub. The inner surface of the propeller housing includes a shoulder formed therein. The outer rim of the locking ring engages the shoulder in order to prevent removal of the propeller housing from the central hub. A locking nut is mountable on the propeller shaft for retaining the locking ring on the propeller shaft. A washer may be disposed between the locking ring and the locking nut for preventing the locking nut from being rotated by the propeller housing.
Each key has a first narrow end and a second wider end, and each keyway of the propeller housing includes a first wide end and a second narrow end such that the wide end of each keyway receives a narrow end of a corresponding key of the central hub as the propeller housing is axially slid onto the hub. As is conventional, the propeller housing includes an outer surface and a plurality of circumferentially spaced propeller blades extending therefrom.
In accordance with a further aspect of the present invention, a propeller assembly is provided for mounting on a rotatable propeller shaft of a watercraft. The propeller assembly includes a central hub mounted on the propeller shaft for rotational movement therewith. The central hub defines a generally cylindrical outer surface having a plurality of circumferentially spaced keys therealong. Each key has a first, narrow end, and a second, wider outer end. A generally tubular propeller housing is slidable onto the central hub for rotational movement with the propeller shaft. The propeller housing includes an inner surface having a plurality of circumferentially spaced pairs of axially extending lobes therealong. Each pair of lobes defines a corresponding keyway receiving a corresponding key along the central hub. A stop member is mounted to the outer end of one of the keys. The stop member limits movement of the propeller housing onto the central hub.
A locking ring is mountable on the propeller shaft. The locking ring includes a generally central disc having an aperture for receiving the propeller shaft therethrough and an outer rim for engaging on a shoulder along the inner surface of the propeller housing in order to prevent removal of the propeller housing from the central hub. A locking nut is mountable on the propeller shaft for retaining the locking ring on the propeller shaft. A washer may be disposed between the locking ring and the locking nut for preventing the locking nut from being rotated by the propeller housing.
Each keyway of the propeller housing includes a wide end and a second narrow end such that the wide end of each keyway receives a narrow end of a corresponding key of the central hub as the propeller housing is axially slid onto the central hub. As is conventional, the propeller housing includes an outer surface having a plurality of circumferentially spaced propeller blades extending therefrom.
In accordance with a still further aspect of the present invention, a propeller assembly is provided for mounting on a rotatable propeller shaft of a watercraft. The propeller assembly includes a central hub mounted on the propeller shaft for rotational movement therewith. A generally tubular propeller housing is slidable into the central hub for rotational movement with the propeller shaft. The propeller housing includes an inner surface having a shoulder formed therein. A locking ring is mountable on the propeller shaft. The locking ring includes a generally circular disc having an aperture for receiving the propeller shaft therethrough and an outer rim for engaging the shoulder and preventing removal of the propeller housing of the central hub.
The central hub defines a generally cylindrical outer surface having a plurality of circumferentially spaced keys therealong. The key has a first, narrow end and a second, wider outer end. The inner surface of the propeller housing includes a plurality of circumferentially spaced pairs of axially extending lobes therealong. Each pair of lobes defines a corresponding keyway for receiving a corresponding key along the central hub. Each keyway of the propeller housing includes a first wide end and a second narrow end such that the wide end of each keyway receives a narrow end of a corresponding key of the central hub of the propeller housing as the propeller housing is axially slid onto the central hub. A stop member is mounted to the outer end of one of the keys. The stop member limits movement of the propeller housing onto the central hub.
A locking nut is mounted on the propeller shaft for retaining the locking ring on the propeller shaft. A washer may be disposed between the locking ring and the locking nut for preventing the locking nut from being rotated by the propeller housing.